It has been conventional to make panels for use in automobiles or the like made up of two components that must have the requisite strength and rigidity to meet functional performance characteristics yet be relatively light in weight. To keep the overall panel weight as light as possible, configurations such as various rib patterns and protrusions in the sheet forming the structural support for the panel have been employed. One such approach is an array of shapes such as frusta of cones, but these are limited in depth and angle by the formability of the metal and also require use of expensive matched forming dies. Such arrangements result in undesirable areas of stress concentrations, especially at the juncture of the sidewalls with adjacent planar portions. Another deficiency with respect to these types of constructions is that these shapes may result in "visible" patterns on the outer panel sheet, which is not aesthetically acceptable.